Wood's lamp examination

Definition

A Wood's lamp examination is a test that uses ultraviolet (UV) light to look at the skin closely.

Alternative Names

Black light test; Ultraviolet light test

How the test is performed

You will sit in a dark room for this test. The test usually takes place in a dermatologist's office. The health care provider will turn on the Wood's lamp and hold it 4 - 5 inches from the skin to look for color changes.

How to prepare for the test

You do not need to take any special steps before this test. Ask your doctor if you avoid putting creams or medicines on the area of the skin being studies before the test.

How the test will feel

You will feel nothing during this test.

Why the test is performed

Your health care provider may do this to look for skin problems including: